JPH02155401A - Auxiliary power supply device for electric vehicle - Google Patents

Abstract

PURPOSE:To maintain an output voltage substantially constant and to reduce the number of components and size by providing gain switching means for maintaining the output voltage of a transformer with taps constant, and controlling the phase of an inverter with a full-bridge structure. CONSTITUTION:The intermediate tap side and a winding end sides of a transformer 7 are switched by a converter 5 in response to a rated trolley wire voltage detected by a voltage detector 21. A full-bridge inverter 14 is composed of four sets of switching elements 14A - 14D, and the gain of a phase control circuit 20 is so switched as to generate the same rated voltage at the secondary side of the transformer 7 in response to a trolley wire voltage. Thus, the output voltage of the inverter 14 can be kept substantially constant. The number of components can be reduced to 1/2 - 1/4 of that of the conventional one, and its size can be reduced.

Description

Detailed Description of the Invention [Objective of the Invention] (Industrial Application Field) The present invention provides an auxiliary power supply device for a dual voltage input type electric vehicle, which can run on both a 600V overhead line section and a 1500V overhead line section, for example. The present invention relates to an auxiliary power supply device provided for battery charging, etc. in an electric vehicle.

(Prior Art) Electric vehicles are often provided with an auxiliary power supply device for charging a battery to a constant voltage regardless of the overhead line voltage. FIG. 3 shows this type of conventional auxiliary power supply device for electric vehicles.

In the auxiliary power supply device shown in FIG.
Set of glue handles 4A, 4B and two sets of converter contacts 5A
, 5B to two sets of half-bridge type inverters 6
A and 6B, where DC power is converted to AC power. Both inverters 6A and 6B have two sets of converter contacts 5C,
They are interconnected by 5D. In the following description, 600V and 1500V are assumed as the rated voltage of the overhead wire 1. Each converter contact 5A, 5B, 5C, 5D is switched according to the rated voltage of the overhead line 1, and when the rated voltage of the overhead line 1 is relatively low 600V, two sets of glue handles 4A,
4B and two sets of inverters 6A and 6B are connected in parallel, respectively, and in the case of a relatively high voltage of 1500V, they are switched to be connected in series. The figure shows the former parallel connection state. In the case of a series connection, the contact positions are switched to the opposite side from the illustrated contact positions. inverter 6A,
6B is a capacitor 6 constituting one arm phase, respectively.
1, 62, switching elements 63 and 64 with anti-parallel diodes constituting the other arm phase, and a current limiting circuit 65 connected in series between both arm phases. A transformer 7 is installed at each AC output terminal of the inverters 6A and 6B.
A and 7B are connected. The secondary sides of the double pressure converters 7A and 7B are connected in series, and both ends thereof are connected to the AC input terminal of the rectifier 8. DC output end beam handle 9 of rectifier 8
and a load 1 through a smoothing circuit consisting of a capacitor 10.
Connected to 1. The load 11 may be, for example, a battery charging circuit.

The firing phase of each of the switching elements 63 and 64 of the inverters 6A and 6B is controlled by the phase control circuit 20 so that a constant DC voltage is supplied to the load 11. In order to accomplish this voltage control, four sets of voltage detectors 21, 22A, 2
2B and 23 are provided. The voltage detector 21 is connected to the overhead wire 1
voltage detector 22A.

22B detects the input voltages of the inverters 6A and 6B, respectively, and the voltage detector 23 detects the output voltage of the entire auxiliary power supply device, that is, the input voltage of the load 11. Depending on the rated overhead line voltage detected by the voltage detector 21, the converter contacts 5A to 5D are switched via the converter 5 as already described.

The phase control circuit 20 controls the firing of each switching element 63, 64 so that the load voltage detected by the voltage detector 23 remains constant despite fluctuations in the inverter input voltage detected by the voltage detectors 22A, 22B. Control the phase. In addition, gain switching is performed in the phase control circuit 20 according to the rated overhead line voltage detected by the voltage detector 21 so that the output voltage of the inverters 6A and 6B remains constant even if the rated overhead line voltage changes. .

(Problems to be Solved by the Invention) The conventional auxiliary power supply device having the above-mentioned configuration has a disadvantage in that the number of components is increased due to the circuit configuration in order to cope with multiple voltage input.

That is, in the device shown in Fig. 3, 600V and 150V
In order to be able to use it under both voltages of 0V, two sets of glue axles 4A, 4B and two sets of inverters 6A, 6B are installed.
, two sets of transformers 7A, 7B.

Furthermore, the number of parts is large, such as requiring four sets of converter contacts 5A to 5D, which makes the device large and large.
It had become the property of

Furthermore, since the inverters 6A and 6B have a half-bridge configuration, the primary voltage of the transformers 7A and 7B is 1/2 of the overhead line voltage, and the peak value of the current flowing through the switching elements 63 and 64 becomes particularly large when the overhead line voltage is 600V. .

Therefore, an object of the present invention is to provide an auxiliary power supply device for an electric vehicle that can be configured to be small and lightweight with as few parts as possible.

[Structure of the invention]

(Means for Solving the Problems) In order to achieve the above object, the auxiliary power supply device for an electric vehicle of the present invention uses direct current obtained through a pantograph of an electric vehicle that can be used by receiving power from overhead wires with different rated voltages. an inverter with a full bridge configuration that converts electric power into AC power; a tapped transformer having taps according to the rated voltage and connected to the AC output terminal of the inverter; and a tapped transformer connected to the output terminal of the tapped transformer. a rectifier, a first voltage detection means for detecting the rated voltage of the overhead wire, a second voltage detection means for detecting the input voltage of the inverter, a third voltage detection means for also detecting the output voltage of the rectifier, and a third voltage detection means for detecting the output voltage of the rectifier. tap switching means for switching the taps of the tapped transformer so that the rated output voltage is constant according to the rated voltage of the overhead wire detected by the voltage detection means 1; has a gain switching means for switching the gain according to the rated voltage of the overhead wire detected by the first voltage detection means, and the third voltage detection means and a phase control means for controlling the phase of the inverter so that the detected voltage of the inverter is approximately constant.

(Function) According to the above circuit configuration, by making the inverter a full-bridge configuration, the primary voltage of the transformer becomes the same as the overhead line voltage, and the peak voltage of the switching element becomes one half of that of the half-bridge configuration. The current rating of the switching element can be reduced. Furthermore, the number of various parts can be reduced by almost half, and the entire device can be made smaller and lighter.

(Example) Hereinafter, an example of the present invention will be described in more detail with reference to the drawings.

FIG. 1 shows an embodiment of the present invention.

In FIG. 1, DC power obtained from an overhead wire 1 via a pantograph 2 is passed through a smoothing circuit consisting of a circuit breaker 3, a reactor 4 and a capacitor 12, and a current limiting circuit 13 to a voltage type inverter 14 with a full bridge configuration. where it is converted into AC power. The inverter 14 is configured by bridge-connecting four sets of switching elements 14A, 14B, 14C, and 14D each having antiparallel-connected diodes. Inverter 14
A transformer 7 having a tap on the negative side is connected to the AC output end of the transformer 7. Tap switching of the transformer 7 is effected by converter contacts 5A. Tap switching in this case is performed in a no-load state. The AC power taken out from the secondary side of the transformer 7 is converted into DC power by a rectifier W8, and this direct current power beam is connected to an accelerator 9 and a capacitor 10.
The signal is supplied to the load 11 through a switching circuit consisting of the following.

The overhead line voltage and the load voltage are detected by the first to third voltage detectors 21 to 23, respectively, and the voltage of the capacitor 12 is detected as the inverter input voltage by the second voltage detector 22. Converter contact 5
A is determined by the converter 5 depending on the rated overhead line voltage detected by the voltage detector 21, and when the overhead line voltage is 600V, the tap of the transformer 7 is placed on the intermediate tap side, and when the overhead line voltage is 1500V, the tap of the transformer 7 is placed on the end side of the winding. Switching operation is performed. In the diagram, there is a rack! The contact state is shown when the voltage is 600V. As a result, a constant rated voltage always occurs on the secondary side of the transformer 7, regardless of the rated overhead line voltage. Furthermore, according to the rated overhead line voltage detected by the voltage detector 21, the gain of the phase control circuit 20 is switched so that the same rated secondary voltage is generated on the secondary side of the transformer 7. As in the case of the device shown in FIG. 3, voltage fluctuations under each rated voltage are compensated for by feeding back the detected voltage of the voltage detector 23 to the phase control circuit 20.

The auxiliary power supply device configured as described above is characterized by a significant reduction in the number of parts compared to conventional devices. That is, in the case of the device shown in FIG. 1, by providing 1 set of glue handles 4, 1 set of capacitors 12, 1 set of converter contacts 5A, 1 set of current limiting circuits 13, and 1 set of transformer 7, the desired result can be achieved. It can be seen that the power supply device is constructed and the number of individual parts is reduced from one-half to one-fourth compared to the conventional device shown in FIG.

Further, by configuring a full bridge inverter using four sets of switching elements, there is no need to switch between series and parallel input filter circuits, and the circuit configuration can be simplified.

Although the apparatus shown in FIG. 1 has been described as receiving DC power from the overhead wire 1, the present invention is also applicable to an apparatus that receives AC power, converts it into DC power using a rectifier, and supplies the power to an inverter. FIG. 2 shows the main parts of such an AC power receiving type. In FIG. 2, AC power obtained from the overhead wire 1 via the pantograph 2 is once received by a transformer 15, and converted into DC power by a rectifier 16 connected to the secondary side of the transformer 15. After being converted to DC power in this way, it is converted to AC power and reconverted to DC power by each component below circuit breaker 3, similar to the DC power taken out from pantograph 2 in the case of Figure 1. be exposed.

Note that the switching elements constituting the inverter 14 may be ordinary thyristors in addition to self-extinguishing elements such as gate turn-off thyristors (GTOs).

Furthermore, the overhead wire voltage is not limited to the rated voltages of 600 V and 1500 V, and may be multiple voltages of other values.

〔Effect of the invention〕

According to the present invention, by using an inverter with a full bridge configuration for a multiple voltage input horn, one set of inverter and one set of transformer are sufficient, which greatly reduces the number of main circuit components and By simplifying the configuration, it is possible to provide a small and lightweight auxiliary power supply device for electric vehicles.

[Brief explanation of the drawing]

Fig. 1 is a wiring diagram showing the case of direct current power reception of the auxiliary power supply device for electric vehicles according to an embodiment of the present invention, Fig. 2 is a wiring diagram showing the main parts in case of AC power reception, and Fig. m3 is the wiring diagram of the conventional electric car auxiliary power supply device FIG. 3 is a wiring diagram of the auxiliary power supply device. 1... Overhead line, 2... Pantograph, 3... Circuit breaker, 4... Reactor, 5... Converter, 5A... Converter contact, 7... Tap transformer, 8 ... Rectifier, 9... Reactor, 10... Capacitor, 11.
...Load, 12...Capacitor, 13...Current limiting circuit, 14...Full bridge voltage type inverter, 20...
- Phase control circuit, 21... first voltage detector, 22.
...Second voltage detector, 23...Third voltage detector. Applicant's agent Mr. Sato

Claims (1)

[Claims] an inverter having a full bridge configuration that converts DC power obtained through a pantograph of an electric car into AC power by receiving power from overhead wires having different rated voltages; and an inverter having taps corresponding to each of the rated voltages. a tapped transformer connected to the AC output end of the tapped transformer, a rectifier connected to the output end of the tapped transformer, a first voltage detection means for detecting the rated voltage of the overhead wire, and an input voltage of the inverter. a second voltage detection means for detecting the output voltage of the rectifier; a third voltage detection means for detecting the output voltage of the rectifier; and a third voltage detection means for detecting the output voltage of the rectifier; tap switching means for switching the taps of the tapped transformer so that the rated output voltage is constant; The inverter has a gain switching means for switching the gain and controls the phase of the inverter so that the detected voltage of the third voltage detecting means is approximately constant despite fluctuations in the detected voltage of the second voltage detecting means. An auxiliary power supply device for an electric vehicle, comprising a control means.